Máscaras caseiras na pandemia de COVID-19: recomendações, características físicas, desinfecção e eficácia de uso / Mascarillas caseras en la pandemia de COVID-19: recomendaciones, características físicas, desinfección y eficacia de uso / Homemade masks in the COVID-19 pandemic: recommendations, physical characteristics, disinfection and efficacy

Objetivo: Descrever as recomendações, características físicas, métodos de desinfecção e eficácia de uso de máscaras caseiras na redução da transmissão da COVID-19. Métodos: Realizou-se busca nas bases de dados MEDLINE, SciELO e Google Scholar, além das recomendações oficiais de uso. Resultados: Foram incluídas 31 referências. A capacidade de filtração de tecidos variou entre 5% e 98%. Tecidos 100% algodão em duas ou três camadas apresentaram eficácia de filtração entre 70% e 99% em estudos in vitro. Máscaras caseiras, cirúrgicas e respiradores apresentaram respirabilidade entre 2,2 e 3,0 Pascal. A capacidade de redução da propagação de microrganismos por pessoas usando máscaras caseiras foi três vezes menor do que usando máscaras cirúrgicas, embora tenha sido superior ao não uso de máscaras. Conclusão: A respirabilidade de máscaras caseiras mostrou-se adequada, enquanto a capacidade de filtração parece ser inferior à das máscaras cirúrgicas, mas superior a não se usar máscara. Não há evidências que respaldem a eficácia e efetividade das máscaras caseiras.

Objetivo: Describir las recomendaciones, características físicas, métodos de desinfección y efectividad de mascarillas caseras para reducir la transmisión de COVID-19. Métodos: La búsqueda se realizó en las bases de datos MEDLINE, SciELO y Google Scholar, además de las recomendaciones oficiales de uso. Resultados: Se incluyeron 31 referencias. La capacidad de filtración de los tejidos varió entre 5% y 98%. Los tejidos al 100% de algodón, en dos o tres capas, mostraron eficiencia de filtración entre 70% y 99%, en estudios in vitro. Mascarillas caseras, quirúrgicas y de respiradores mostraron respirabilidad entre 2,2 y 3,0 Pascal. La capacidad de reducir la propagación de microorganismos por personas que usan máscarillas caseras fue tres veces menor que cuando usaban mascarillas quirúrgicas, pero superior a no usarlas. Conclusión: La respirabilidad de las mascarillas caseras puede ser adecuada, mientras que la eficiencia de filtración parece ser inferior a la de las mascarillas quirúrgicas, pero superior a no utilizar mascarilla. No hay evidencia que respalde su eficacia y efectividad.

Objective: To describe the recommendations, physical characteristics, disinfection methods and efficacy of the use of homemade face masks to reduce COVID-19 transmission. Methods: We searched MEDLINE, SciELO, and Google Scholar, in addition to the official recommendations for the use of masks. Results: Thirty-one references were included. Fabric filtration efficiency ranged from 5% to 98%. The filtration efficacy of three layered 100% cotton fabric face masks ranged from 70% and 99% in vitro studies. Homemade, surgical, and respirator masks showed breathability between 2.2 and 3.0 Pascal. The capacity to reduce the spread of microorganisms by people wearing homemade face masks was three times lower when compared to those wearing surgical masks, although this capacity was higher when compared to those who did not wear masks. Conclusion: The breathability of homemade masks proved to be adequate, while the filtration ability seemed to be lower than that of surgical masks, but it was better than not wearing any masks at all. There is no evidence to support the efficacy and effectiveness of homemade masks.

Do Various Respirator Models Fit the Workers in the Norwegian Smelting Industry?

BACKGROUND: Respirator fit testing is a method to assess if the respirator provides an adequate face seal for the worker. METHODS: Workers from four Norwegian smelters were invited to participate in the study, and 701 respirator fit tests were performed on 127 workers. Fourteen respirator models were included: one FFABE1P3 and 11 FFP3 respirator models produced in one size and two silicone half masks with P3 filters available in three sizes. The workers performed a quantitative fit test according to Health and Safety Executive 282/28 with 5–6 different respirator models, and they rated the respirators based on comfort. Predictors of overall fit factors were explored. RESULTS: The pass rate for all fit tests was 62%, 56% for women, and 63% for men. The silicone respirators had the highest percentage of passed tests (92–100%). The pass rate for the FFP3 models varied from 19–89%, whereas the FFABE1P3 respirator had a pass rate of 36%. Five workers did not pass with any respirators, and 14 passed with all the respirators tested. Only 63% passed the test with the respirator they normally used. The mean comfort score on the scale from 1 to 5 was 3.2. The respirator model was the strongest predictor of the overall fit factor. The other predictors (age, sex, and comfort score) did not improve the fit of the model. CONCLUSION: There were large differences in how well the different respirator models fitted the Norwegian smelter workers. The results can be useful when choosing which respirators to include in respirator fit testing programs in similar populations.